Facilitating supplemental disinfection for Legionella control in plumbing systems

摘要

Slight changes to the way supplemental disinfection is currently regulated could lead to reductions in legionellosis and other diseases without a significant impact on other important drinking water quality parameters.nRegrowth of microorganisms is a common occurrence in treated water in distribution. The significant concern is that certain of those microorganisms, including Legionella pneumophila, are known pathogens and have caused disease and deaths-probably at an increasing rate. The risk of acquiring legionellosis from waterborne aerosol inhalation exposures is now the most significant waterborne-disease risk associated with distributed drinking water in the United States. The Centers for Disease Control (CDC) reported in 2009-2010 that there were 33 waterborne-disease outbreaks, 19 of which were from Legionella in plumbing systems or of drinking water supply origin, resulting in 105 cases and 14 deaths (CDC MMWR, 2013). These were the only outbreaks that reported deaths. US legionellosis cases reported annually increased 217%, from 1,110 in 2000 to 3,522 in 2009 (CDC MMWR, 2011). An estimated 8,000 to 18,000 people are hospitalized with Legionnaires'-related disease each year in the United States (CDC, 2013). Some unknown portion of those estimated cases were associated directly or indirectly with a drinking water-related exposure by elderly and immune-suppressed people and possibly smokers, in hospitals and long-term care, and perhaps associated with hotels, apartment buildings, cooling-system heat exchangers, humidifiers, or even home plumbing.